In his seven-decade career, Dave Brubeck was an artistic and a commercial success, a pianist and composer who expanded the musical landscape and who crossed other borders as one of the world’s foremost ambassadors of jazz.

He had an inventive style that brought international music into the jazz mainstream, but he was more than a musical innovator: He was an American original.

Mr. Brubeck died Wednesday at a hospital in Norwalk, Conn., one day before his 92nd birthday. His manager, Russell Gloyd, said Mr. Brubeck was on his way to a regular checkup with his cardiologist when his heart gave out.

Considered one of the greatest figures of a distinctively American art form, Mr. Brubeck was a modest man who left a monumental legacy. His 1959 recording “Time Out,” with its infectious hit “Take Five,” became the first jazz album to sell 1 million copies. He toured once-forbidden countries in the Middle East and in the old Soviet empire and was honored by presidents and foreign dignitaries.

He wrote hundreds of tunes, including the oft-recorded “In Your Own Sweet Way” and “The Duke.” His quartet, featuring alto saxophonist Paul Desmond, was one of the most popular jazz groups in history, and he kept up a busy performing schedule into his 90th year.

He also composed ambitious classical and choral works, released nearly 100 albums and remained a charismatic and indefatigable performer into old age. In December 2010, the month Mr. Brubeck turned 90, his quartet won the readers’ poll of DownBeat magazine as the best group in jazz, 57 years after he first won the poll.

A bespectacled cowboy who grew up on a remote California ranch, Mr. Brubeck was known for his complex rhythmic patterns, which he said were inspired by riding his horse and listening to its syncopated hoofbeats striking the ground.

He studied in the 1940s with the experimental French composer Darius Milhaud, who encouraged his interest in jazz. Mr. Brubeck was among the first jazz musicians to make wide use of polytonality, or playing in more than one musical key at a time. He was also an early advocate of “world music,” adopting exotic sounds that he heard in his worldwide travels.

After forming his quartet in California in the early 1950s, he sought to branch out from the dank nightclubs of San Francisco and Los Angeles. His wife, Iola, suggested the quartet perform on college campuses, which produced a nationwide sensation, with record sales to match.

“We reached them musically,” he told The New York Times in 1967. “We had no singers, no beards, no jokes. All we presented was music.”

With their curly hair and horn-rimmed glasses, Desmond and Mr. Brubeck looked like professorial brothers and were unlikely jazz stars. The two had an instant musical bond and could anticipate each other’s bandstand improvisations, as Desmond’s ethereal, upper-register saxophone soared above Mr. Brubeck’s driving keyboard attack.

With the release of “Time Out” in 1959, Mr. Brubeck had the first jazz album to sell more than 1 million copies. It reached No. 2 on the pop charts, and its eternally catchy signature tune, “Take Five,” became a surprise hit.

The tune, written by Desmond but heavily arranged by Mr. Brubeck, built a memorable melody over a complex rhythm in the unusual time signature of 5/4. “Take Five” became a staple of his concerts and helped make the Dave Brubeck Quartet the most popular jazz group of the 1950s and ’60s.

“Every once in a while,” jazz historian and critic Ted Gioia wrote in an email exchange with The Washington Post, “jazz is blessed by one of those great figures who can do it all. They give us a body of work that is full of musical riches … but the music also can appeal to the average listener. Dave Brubeck is one of those figures.”

“Cool jazz”

Mr. Brubeck’s position in musical history has often been debated. He was born the same year as Charlie Parker, the tortured genius of the bebop movement who brought a new rhythmic and harmonic sophistication to jazz in the 1940s, but Mr. Brubeck was never a true bebopper. He defied the raffish image of the jazz musician by being a clean-living family man who lived with his wife and six children.

He was considered a seminal force in the West Coast’s understated “Cool Jazz” school of the 1950s, but he disdained the “Cool Jazz” label and preferred to forge an original musical path.

After early struggles, he was reportedly earning more than $100,000 a year by 1954, the year he became the second jazz musician to be featured on the cover of Time magazine (after Louis Armstrong in 1949).

Some musicians and critics resented his success, and others questioned his prominence in a form of music that was created primarily by black musicians.

But Mr. Brubeck was an outspoken advocate of racial harmony and often used his music as a platform for cross-cultural understanding. He once canceled 23 of 25 concerts in the South when local officials would not allow his African-American bass player, Eugene Wright, to appear with the rest of the group.

On a tour in the Netherlands in the 1950s, African-American pianist Willie “The Lion” Smith was asked, in Mr. Brubeck’s presence, “Isn’t it true that no white man can play jazz?”

Smith gestured toward Mr. Brubeck and said to the reporter, “I’d like you to meet my son.”

In 1958, Mr. Brubeck and his quartet undertook an international tour for the State Department, spreading the improvisatory spirit of jazz to Iran, Iraq, Afghanistan, Pakistan, Turkey and Sri Lanka, among other countries. In Poland, they were among the first U.S. jazz musicians to perform behind the Iron Curtain.

In each new country, Mr. Brubeck mingled with musicians, absorbing local rhythms and melodies. Long before the term “world music” gained currency, he was writing compositions that borrowed elements he had heard in Mexico, Japan, Turkey, India, Afghanistan and other countries.

Cowboy childhood

David Warren Brubeck was born Dec. 6, 1920, in Concord, Calif. He and his family lived on a 45,000-acre ranch near Ione.

His father was a champion rodeo roper and his mother was a conservatory-trained pianist who had studied in London with concert star Dame Myra Hess. She gave her three sons a surprisingly advanced musical education, and his two older brothers, Henry and Howard, became music teachers and composers.

Because of early eyesight problems, Mr. Brubeck always had difficulty reading musical notation. He compensated by learning to improvise and to play by ear, which served him well in jazz.

At the University of the Pacific in Stockton, Calif., he had planned to study veterinary medicine. But a zoology professor saw how much time he spent in the music department and suggested he change majors.

A dean called him a disgrace but allowed him to graduate after a professor pleaded on his behalf, calling him a budding genius.

In college, Mr. Brubeck proposed on his first date with Iola Whitlock, and the two were married in 1942.

During World War II, Mr. Brubeck was pulled from the ranks of an infantry unit by an Army colonel, who asked him to start a jazz band to entertain troops on the front lines.

After the war, he did graduate work at Mills College in Oakland, Calif., with Milhaud and wrote and performed avant-garde jazz.

Drummer Joe Morello joined Mr. Brubeck and Desmond in 1956, followed by Wright in 1958, forming a group that recorded dozens of records and found international acclaim. The quartet had a huge following until it split up in 1967.

Besides his wife, of Wilton, Conn., survivors include his four sons and a daughter. One son died in 2009.

In the early 1980s, Mr. Brubeck formed a new quartet, with which he toured until shortly before his death. In 1996, he won a Grammy Award for lifetime achievement, and he was a Kennedy Center Honoree in 2009.